diff options
| author | John Hawthorn <[email protected]> | 2025-07-17 10:05:12 -0700 |
|---|---|---|
| committer | John Hawthorn <[email protected]> | 2025-07-17 11:50:13 -0700 |
| commit | cb33f22f5b64b4d12cda7b7222898c3b20438fcc (patch) | |
| tree | c0a7afc83b91c69c0ae0f83a009e55a6d1cd512f | |
| parent | 39b844e06463d32a13b042f6f8229f2ea9f6c7d4 (diff) | |
This issues writebarriers for objects added via gc_offsets or by
profiling. This may be slower than writebarrier_remember, but we would
like it to be more debuggable.
Co-authored-by: Max Bernstein <[email protected]>
Co-authored-by: Stan Lo <[email protected]>
| -rw-r--r-- | zjit/src/codegen.rs | 8 | ||||
| -rw-r--r-- | zjit/src/gc.rs | 17 | ||||
| -rw-r--r-- | zjit/src/profile.rs | 7 |
3 files changed, 24 insertions, 8 deletions
diff --git a/zjit/src/codegen.rs b/zjit/src/codegen.rs index 8c9bf5d4d1..6d8692840e 100644 --- a/zjit/src/codegen.rs +++ b/zjit/src/codegen.rs @@ -4,7 +4,7 @@ use std::rc::Rc; use crate::asm::Label; use crate::backend::current::{Reg, ALLOC_REGS}; use crate::invariants::track_bop_assumption; -use crate::gc::get_or_create_iseq_payload; +use crate::gc::{get_or_create_iseq_payload, append_gc_offsets}; use crate::state::ZJITState; use crate::{asm::CodeBlock, cruby::*, options::debug, virtualmem::CodePtr}; use crate::backend::lir::{self, asm_comment, asm_ccall, Assembler, Opnd, SideExitContext, Target, CFP, C_ARG_OPNDS, C_RET_OPND, EC, NATIVE_STACK_PTR, SP}; @@ -124,7 +124,7 @@ fn gen_iseq_entry_point_body(cb: &mut CodeBlock, iseq: IseqPtr) -> *const u8 { // Remember the block address to reuse it later let payload = get_or_create_iseq_payload(iseq); payload.start_ptr = Some(start_ptr); - payload.gc_offsets.extend(gc_offsets); + append_gc_offsets(iseq, &gc_offsets); // Compile an entry point to the JIT code (gen_entry(cb, iseq, &function, start_ptr, jit.c_stack_bytes), jit.branch_iseqs) @@ -193,7 +193,7 @@ fn gen_iseq(cb: &mut CodeBlock, iseq: IseqPtr) -> Option<(CodePtr, Vec<(Rc<Branc let result = gen_function(cb, iseq, &function); if let Some((start_ptr, gc_offsets, jit)) = result { payload.start_ptr = Some(start_ptr); - payload.gc_offsets.extend(gc_offsets); + append_gc_offsets(iseq, &gc_offsets); Some((start_ptr, jit.branch_iseqs)) } else { None @@ -999,7 +999,7 @@ fn gen_guard_type(jit: &mut JITState, asm: &mut Assembler, val: lir::Opnd, guard /// Compile an identity check with a side exit fn gen_guard_bit_equals(jit: &mut JITState, asm: &mut Assembler, val: lir::Opnd, expected: VALUE, state: &FrameState) -> Option<lir::Opnd> { - asm.cmp(val, Opnd::UImm(expected.into())); + asm.cmp(val, Opnd::Value(expected)); asm.jnz(side_exit(jit, state, GuardBitEquals(expected))?); Some(val) } diff --git a/zjit/src/gc.rs b/zjit/src/gc.rs index 23e2003661..01bcc9fe5d 100644 --- a/zjit/src/gc.rs +++ b/zjit/src/gc.rs @@ -90,6 +90,23 @@ pub extern "C" fn rb_zjit_iseq_mark(payload: *mut c_void) { } } +/// Append a set of gc_offsets to the iseq's payload +pub fn append_gc_offsets(iseq: IseqPtr, offsets: &Vec<CodePtr>) { + let payload = get_or_create_iseq_payload(iseq); + payload.gc_offsets.extend(offsets); + + // Call writebarrier on each newly added value + let cb = ZJITState::get_code_block(); + for &offset in offsets.iter() { + let value_ptr: *const u8 = offset.raw_ptr(cb); + let value_ptr = value_ptr as *const VALUE; + unsafe { + let object = value_ptr.read_unaligned(); + rb_gc_writebarrier(iseq.into(), object); + } + } +} + /// GC callback for updating GC objects in the per-iseq payload. /// This is a mirror of [rb_zjit_iseq_mark]. #[unsafe(no_mangle)] diff --git a/zjit/src/profile.rs b/zjit/src/profile.rs index 4b5c7b60d4..7db8e44c7a 100644 --- a/zjit/src/profile.rs +++ b/zjit/src/profile.rs @@ -88,11 +88,10 @@ fn profile_operands(profiler: &mut Profiler, profile: &mut IseqProfile, n: usize for i in 0..n { let opnd_type = Type::from_value(profiler.peek_at_stack((n - i - 1) as isize)); types[i] = types[i].union(opnd_type); + if let Some(object) = types[i].gc_object() { + unsafe { rb_gc_writebarrier(profiler.iseq.into(), object) }; + } } - // In the loop above, we probably added a new reference to the profile through - // the VALUE in Type. It's messy and relatively slow to conditionally run a - // write barrier for each Type, so just remember to re-mark the iseq. - unsafe { rb_gc_writebarrier_remember(profiler.iseq.into()) }; } #[derive(Debug)] |
